[ Implementing a Phase Shift block ]

Hi Marcus,

wrote it, as I could not find it in the GRC.
block.

If you want to do coarser phase shifts (large multiples of 180deg), you
can use a delay block.

Presently I’m calculating the delay between two synchronised signals
coming
out of the USRP source (connected to a signal generator) by recording
their
samples and finding the offset between their first peak or
zero-crossing.

Now if we want to time-align them in real-time, how can we implement a
delay block that calculates the delay each time the grc flow is run and
set
the delay_value in the block accordingly so that they are time-aligned?
i.e
I don’t want to record the samples rather I’d like to know how to find
the
delay and shift any of the two signals so that they get aligned?

Best,

Normally, this kind of delay detection is done using cross-correlation
(or
some more applicable variant thereof such as MRC). Note also that a
delay
will give a frequency-dependent phase shift, so you may wish to use a
delay
block rather than phase shift if your signal is broadband (although I
must
admit I don’t know what the phase shift block does internally).